Gmail, Yahoo and Outlook bulk sender requirements: the 2026 checklist
6 min read · Published · Password and DNS Toolbox
Short answer
If you send around 5,000 or more messages a day to Gmail or Outlook.com users, you need SPF, DKIM, a DMARC record (at least p=none) with an aligned From domain, one-click unsubscribe for marketing mail, and a spam complaint rate below 0.3%. Yahoo applies the same authentication and unsubscribe rules without publishing a volume threshold.
Key points
- All senders to Gmail need SPF or DKIM, valid forward and reverse DNS, and TLS.
- Bulk senders additionally need SPF, DKIM, DMARC and alignment, plus one-click unsubscribe.
- Google has tightened enforcement since November 2025: non-compliant mail can be rejected.
Gmail
Google defines bulk senders as those sending 5,000 or more messages a day to Gmail accounts. Requirements took effect in February 2024, and Google has been ramping up enforcement since November 2025 with temporary and permanent rejections.
- All senders: SPF or DKIM, valid forward and reverse DNS for sending IPs (check PTR records), TLS, and a spam rate below 0.3%.
- Bulk senders: SPF and DKIM, DMARC with at least
p=none, From domain aligned with SPF or DKIM, one-click unsubscribe (RFC 8058) for marketing mail. Google recommends keeping the spam rate below 0.1%.
Yahoo
Yahoo requires SPF and DKIM, a DMARC record of at least p=none that passes (relaxed alignment is fine), unsubscribes honoured within two days, and a spam rate below 0.3%. It strongly recommends RFC 8058 one-click unsubscribe.
Outlook.com, Hotmail and Live
Microsoft applies similar rules to domains sending more than 5,000 messages a day to its consumer services: SPF and DKIM must pass and a DMARC record of at least p=none must exist and align. Non-compliant mail is rejected with the error 550 5.7.515.
Checklist with free tools
| Requirement | How to check |
|---|---|
| SPF passes, under 10 lookups | SPF checker |
| DKIM key published, 2048-bit | DKIM lookup |
| DMARC record present | DMARC checker |
| Alignment on real mail | Header analyzer |
| Sending IP has forward-confirmed PTR | Reverse IP lookup |
| Sending IP not on blocklists | Blacklist checker |
Frequently asked questions
Do the rules apply to small senders?
Gmail's basic rules (SPF or DKIM, reverse DNS, TLS, low spam rate) apply to everyone. The DMARC and unsubscribe rules target bulk senders, but following them helps everyone's deliverability.
What is one-click unsubscribe?
A List-Unsubscribe header with an HTTPS link plus List-Unsubscribe-Post: List-Unsubscribe=One-Click (RFC 8058), so mail apps can unsubscribe with one button.
Is p=none really enough?
It meets the current minimum. Moving to quarantine or reject gives real protection and is required for BIMI logos.